There are applications where a DC offset inhibits performance thereby being unacceptable from a performance perspective.
The foremost applications for the present invention are Homodyne RF and high-end audio, but other areas might benefit as well. The most benefit is when there is a need to compensate for slow drifts like temperature.
Presently known solutions can generally be divided into two different approaches. One approach is continuously used where a high pass filter is blocking the DC component and letting the AC component pass. This approach will present problems with applications where there are low frequency components in the required signal, which thus will suffer if a high pass filter is coupled in the signal path.
Another approach is used only in the beginning of a process, such as in the set-up of a communication session, where an initial estimation of the DC component will be followed by a fixed compensation value used throughout the process. This latter approach suffers from long-term DC drifts or variations, such as temperature dependent variations, where the fixed compensation value will be unable to compensate for the changed DC component.